Armor-piercing projectiles



ARMOR-PIERCING PROJECTILES Filed Feb. 28, 1959 INVE/V TOR GEORGES DUFOUR7 7 A ATTORNEY United States Patent Ofifice 3,096,715 Patented July 9,1963 3,096,715 ARMOR-PIERCING PROJECTILES Georges Dufour, Geneva,Switzerland, assignor to Brevets Aero-Mecaniques S.A., Geneva,Switzerland, a society of Switzerland Filed Dec. 28, 1959, Ser. No.862,401 Claims priority, application Luxembourg Jan. 19, 1959 3 Claims.(Cl. l02-52) The present invention relates to armor-piercing projectilesfor guns having a barrel provided with rifles, such projectilesincluding a core of a hard material surrounded by an ogive made at leastpartly of a light material, the terms light material" including not onlylight metals and alloys but also all other substances such as plasticmaterials having a density substantially lower than that of steel.

The invention is more especially concerned with armorpiercing shells ofsmall calibre.

The chief object of the present invention is to provide a projectile ofthis type which is better adapted to meet the requirements of practice,not only from the point of view of their armor-piercing properties butalso from the point of view of the preservation of the barrel of the gunfrom which they are fired.

According to this invention, the ogive of such a projectile includes arear portion of a cross-section smaller than the maximum cross-sectionof the front portion of said ogive, this rear portion, which surroundsthe rear portion of the core, being itself surrounded by a base alsomade of a light material, said base including a rearward extensionsurrounded by a ring of a hard material in which is fixed at least onedriving or rotating band for giving the projectile its spin.

A preferred embodiment of the invention will be hereinafter describedwith reference to the accompanying drawing, given merely by way ofexample and in which the only figure illustrates an armor-piercingprojectile of small calibre made according to this invention, one halfbeing shown in elevation and the other half in axial section.

The essential element of this projectile, which is to perform thearmor-piercing function thereof, is a core 1, having a pointed frontend, which should of course store up the maximum possible of kineticenergy under the smallest possible volume so that it is made of a highdensity material (hard sintered metal, tungsten carbide and so on Thepoint of core 1, which is not very sharp, so as to obtain a goodarmor-piercing effect, is covered by an ogive of sharper shape made of alight material such as aluminum or an aluminum alloy, copper ormagnesium, such an ogive improving the ballistic properties of theprojectile and also its armor-piercing action due to the lubricatingeffect exerted when said ogive is crashed against the point of impact.

This ogive includes the following portions: on the one hand, a sharpfront portion 2 adapted to cover the point of the core and whichadvantageously leaves a free space between the ogive and the core inwhich can be packed a burning composition 3, for instance an incendiaryone; this front portion 2 extends to the rear end of the ogive of thecore, behind which said core becomes cylindrical, and on the other hand,a rear portion 4 substantially of cylindrical shape, surrounding therear portion of the core, this rear portion 4 of the ogive being of adiameter smaller than that of the base of front portion 2.

This rear portion 4 of the ogive is engaged in the front portion 5 of abase also made of a light material, this front portion 5 having theshape of a hollow cylinder opened at the front, the outer wall of whichhas a diameter equal to the external diameter of the projectile, whereasits inner wall is a cylindrical wall adapted to fit on the rear portion4 of the ogive.

This base includes, behind its front portion 5, an extension 6 in theform of a hollow cylinder opened at the rear; the outer wall of which isof a diameter smaller than the external diameter of the projectile,whereas its inner wall limits a recess adapted to receive a powdercomposition 7, for instance an incendiary one or a tracing one.

A rear ring 8 of a hard material, for instance of steel, is fitted andsecured, for instance by screwing, around extension 6, the outer wall ofring 8 being of a diameter equal to the external diameter of theprojectile. This ring 8 carries a driving or rotating band 9, forinstance of copper, sintered iron, soft steel or any suitable material,of an external diameter greater than that of the projectile body. Thisband 9 is for instance partly inserted in a groove provided in ring 8.

Advantageously, before fitting the rear portion 4 of the ogive into thefront portion 5 of the base, there is inserted, along the front edge ofsaid rear portion 5, a ring 10 of a hard metal such as steel, this ring10 bearing against a shoulder 11 provided between the front portion 2 ofthe ogive and its rear portion 4. Thus, said ring 10 is finally caughtbetween shoulder 11 and the front edge 12 of the base 5.

Ring 10 is flush with the front portion 2 of the ogive and the activearea of said ring (area in contact with the inner surface of the gunbarrel) projects slightly beyond the outer wall of the portion 5 of theprojectile.

The rear portion of the projectile is guided in the gun barrel by twoportions B and C of ring 10, said portions preferably having a diameterequal to that of the active area of ring 10.

The chief advantages of such a projectile are as follows: the ratio ofthe weight of core 1 to the total weight of the projectile which reachesabout 54% for a 20 mm. shell as above described is very satisfactorysince the armorpiercing projectiles thus obtained have substantially thesame weight as shells of other types to be fired from the same gun; theportions of the projectiles made of light material do not risk to clogthe inner wall of the gun barrel; accuracy of firing, due to the doubleguiding at the front at A and at the rear at B and C, remains unchangedduring the travel of the projectile through the gun barrel.

In a general manner, while I have, in the above description, disclosedwhat I deem to be a practical and efi'icient embodiment of my invention,it should be well understood that I do not wish to be limited thereto asthere might be changes made in the arrangement, disposition and form ofthe parts without departing from the principle of the present inventionas comprehended within the scope of the accompanying claims.

What I claim is:

l. A projectile which comprises, in combination, an armor piercing core,an ogive mounted on said core to surround it, said ogive being made of amaterial of a density much lower than that of said core, said ogivehaving a cylindrical rear portion of a cross section smaller than themaximum cross section of its front portion, the outer wall of said ogiveforming, between said front portion and said rear portion thereof, arearwardly facing annular shoulder, a cylindrical base fitting tightlyaround said ogive rear portion, said base being made of a material of atleast approximately the same density as said ogive, the front edge ofsaid base being at a distance from said shoulder and facing it, a solidfront guiding ring of a material harder than that of said ogive fittedon the side wall of said rear portion of the ogive, extending from saidshoulder to said base front edge and having an outer diameter slightlygreater than that of said base and that of the outer edge of saidshoulder, a rear cylindrical extension of said base integral therewith,said extension having an outer diameter smaller than that of said base,a rigid rear cylindrical guiding ring fitting tightly around said rearextension, said rear ring being made of a material different from thatof said rear extension and of substantially the same hardness as that ofsaid front ring, said rear ring further having an outer diametersubstantially equal to that of said base and to that of the outer edgeof said shoulder, and a driving band of a metal softer than that of saidguiding rings fixed around said rear ring for giving the projectile itsspin, said driving band having an outer diameter greater than that ofsaid guiding rings and further having an axial length substantially lessthan the axial length of said rear guiding ring.

4 2. A projectile according to claim 1 and further including a powdercharge inserted between the point of the core and the front portion ofthe ogive.

3. A projectile according to claim 1 and further including a powdercharge disposed in a recess formed in said base extension.

References Cited in the file of this patent UNITED STATES PATENTS2,411,073 Whitney Nov. 12, 1946 2,724,334 Norton et a1. Nov. 22, 19552,900,914 Ciccone Aug. 25, 1959 2,975,710 Read Mar. 21, 1961 FOREIGNPATENTS 197,329 Switzerland July 16, 1938 586,174 Great Britain Mar. 10,1947

1. A PROJECTILE WHICH COMPRISES, IN COMBINATION, AN ARMOR PIERCING CORE,AN OGIVE MOUNTED ON SAID CORE TO SURROUND IT, SAID OGIVE BEING MADE OF AMATERIAL OF A DENSITY MUCH LOWER THAN THAT OF SAID CORE, SAID OGIVEHAVING A CYLINDRICAL REAR PORTION OF A CROSS SECTION SMALLER THAN THEMAXIMUM CROSS SECTION OF ITS FRONT PORTION, THE OUTER WALL OF SAID OGIVEFORMING, BETWEEN SAID FRONT PORTION AND SAID REAR PORTION THEREOF, AREARWARDLY FACING ANNULAR SHOULDER, A CYLINDRICAL BASE FITTING TIGHTLYAROUND SAID OGIVE REAR PORTION, SAID BASE BEING CMADE OF A MANTERIAL OFAT LEAST APPROXIMATELY THE SAME DENSITY AS SAID OGIVE, THE FRONT EDGE OFSAID BASE BEING AT A DISTANCE FROM SAID SHOULDER AND FACINT IT, A SOLIDFRONT GUIDING RING OF A MATEIRAL HARDER THAN THAT OF SAID OGIVE FITTEDON THE SIDE WALL OF SAID REAR PORTION OF THE OGIVE, EXTENDING FROM SAIDSHOULDER TO SAID BASE FRONT EDGE AND HAVING AN OUTER DIAMETER SLIGHTLYGREATER THAN THAT OF SAID BASE AND THAT OF THE OUTER EDGE OF SAIDSHOULDER, A REAR CYLINDRICAL EXTENSION OF SAID BASE INTEGRAL THEREWITH,SAID EXTENSION HAVING AN OUTER DIAMETER SMALLER THAN THAT OF SAID BASE,A RIGID REAR CYLINDRICAL GUIDING RING FITTING TIGHTLY AROUND SAID REAREXTENSION, SAID REAR RING BEING MADE OF A MATERIAL DIFFERENT FROM THATOF SAID REAR EXTENSION AND OF SUBSTANTIALLY THE SAME HARDNESS AS THAT OFSAID FRONT RING, SAID REAR RING FURTHER HAVING AN OUTER DIAMETERSUBSTANTIALLY EQUAL TO THAT OF SAID BASE AND TO THAT OF THE OUTER EDGEOF SAID SHOULDER, AND A DRIVING BAND OF A METAL SOFTER THAN THAT OF SAIDGUIDING RINGS FIXED AROUND SAID REAR RING FOR GIVING THE PROJECTILE ITSSPIN, SAID DRIVING BAND HAVING AN OUTER DIAMETER GREATER THAN THAT OFSAID GUIDING RINGS AND FURTHER HAVING AN AXIL LENGTH SUBSTANTIALLY LESSTHAN THE AXIAL LENGTH OF SAID REAR GUIDING RING.